Case IH 1071-06 - VCM – VCM: Fan control solenoid current high

The control module has detected an electrical anomaly—specifically a short circuit to 12V, a short to ground, or an excessive current draw—in the Vistronic engine cooling fan driver circuit. When the current is too high, the ECU drive can overheat, triggering the fault and often causing the fan to default to a continuous 'on' state or cycle erratically.

• MAGNUM AFS Connect
• Magnum 235
• Magnum 250
• Magnum 260
• Magnum 280
• Magnum 290
• Magnum 310
• Magnum 315
• Magnum 340
• Magnum 370
• Magnum 380
• Magnum 400
• Steiger 400
• Steiger 450
• Steiger 500 Quadtrac
• Steiger 595
• MXM120
• MXM130
• MXM190
• MX180
• MX200
• MX285
• Maxxum 100-140
• Maxxum 125
• Puma 165

1. 1

   Unplug the Vistronic fan harness (Harness Disconnect Test). The fan should default to running at full speed when unpowered. If it does, the mechanical portion of the clutch is likely okay, pointing to an electrical issue.

2. 2

   Locate the fan plug near the valve cover and perform a wiring and voltage check. Check for proper power, the 5V reference signal, and verify both grounds.

3. 3

   Inspect the Vistronic fan wire harness for chafing, melting, or pinched wires that could cause a short to 12V or a short to ground.

4. 4

   Verify with a dealer if a VCM/Engine software update is available to correct fan cycling parameters (particularly noted on Magnum 340s) before replacing hard parts.

1. 1

   Preparation

   Turn off the engine, remove the key, and allow the engine and radiator assembly to cool completely.

2. 2

   Remove the Fan Belt

   Relieve tension on the fan belt using the tension pulley assembly. Caution: Do not loosen the tension pulley lock bolt to such an extent that the bolt is completely removed. Slip the belt off the fan pulley.

3. 3

   Disconnect Electrical

   Unplug the Vistronic fan wire harness from the main engine harness.

4. 4

   Remove the Fan Assembly

   Unbolt the fan clutch assembly from the mounting hub. Carefully extract the fan and clutch assembly from the fan shroud area.

5. 5

   Transfer the Fan Blade

   If you are only replacing the viscous clutch, unbolt the fan blade from the old clutch and bolt it onto the new clutch assembly.

6. 6

   Installation

   Position the new fan clutch assembly and bolt it to the hub.

7. 7

   Reinstall the Belt

   Route the fan belt back over the pulleys and reapply tension. Before starting the engine, turn the fan by hand to check for smooth rotation and ensure there is no abnormal bearing sound or binding.

8. 8

   Reconnect and Clear Codes

   Plug in the Vistronic fan wire harness. Use a diagnostic tool to clear the 1071-06 / VCM fault codes and run the tractor to operating temperature to verify the fan cycles correctly.